Over the last month I’ve had users reporting that they’re only receiving emails on their devices every 15 minutes, then receiving several at once. A lot of these users are frequent travellers and rely on emails being received and sent almost instantly.

We have two separate domains each with a BES server, and both are suffering from this issue. Both servers are running BES version 4.1.6.9 and have been for about a year, up until about a month ago this was working perfectly.

The subject of your post is a bit misleading. "Reconciling" in Blackberry language means the update of the status or location of a mail. If you, for example, read a mail in Outlook, it might take 15 to 20 minutes until it is marked as "read" on the Blackberry. So, yes, reconciliation might take up to 20 minutes, that is quite normal.

But new mails coming in have nothing to do with reconciliation, this is a different process and it should happen almost instantly.

It looks to me like the BES does not get notification of new mails through Exchange and only detects new mails through a scan every 15 minutes. This could have happened due to some Exchange/Windows hotfix.